Slaughterhouses, human waste treatment plants, and other types of bio-industry use dryers to transform liquid waste into “solid” (powdery) waste and sell it as an agricultural “co-product.” The ultrafine particles of these co-products blow off trucks during transport and during application to farms as fertilizer, causing respiratory and other human health issues.

Regulations around this issue

Classifying waste as a “co-product that is beneficial to soil” is a way for industrial operations to avoid regulation. A co-product means the waste is not classified as waste, but instead as a fertilizer. Pennsylvania’s DEP will not investigate agricultural issues.

The US EPA Office of Water (OW) regulates biosolids. The regulations, 40 CFR Part 503, are usually referred to as the 503s. Despite the agency’s claim to the contrary, OW also promotes land application.

There are no federal environmental air quality regulations on ultrafine particles.